US6973392B2 - Method of determining the imbalance of a laundry drum - Google Patents

Method of determining the imbalance of a laundry drum Download PDF

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Publication number
US6973392B2
US6973392B2 US11/040,805 US4080505A US6973392B2 US 6973392 B2 US6973392 B2 US 6973392B2 US 4080505 A US4080505 A US 4080505A US 6973392 B2 US6973392 B2 US 6973392B2
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United States
Prior art keywords
direct current
drum
imbalance
drive motor
intermediate circuit
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Expired - Fee Related
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US11/040,805
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US20050143940A1 (en
Inventor
Stefan Zeh
Martin Weinmann
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Diehl AKO Stiftung and Co KG
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Diehl AKO Stiftung and Co KG
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    • D—TEXTILES; PAPER
    • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
    • D06F34/00—Details of control systems for washing machines, washer-dryers or laundry dryers
    • D06F34/14—Arrangements for detecting or measuring specific parameters
    • D06F34/16—Imbalance

Definitions

  • the invention pertains to a method of determining a characteristic value for the imbalance of a laundry drum of a washing machine.
  • the drum is driven by an electric drive motor about an at least approximately horizontal axis.
  • the characteristic value is determined by measuring the periodic fluctuation in the electrical power consumption (dP/dt) of its drive motor.
  • the prior art method of evaluating the imbalance of a loaded washing machine drum therefore involves measuring the rotary speed fluctuation caused by the imbalance in the course of a revolution, with soft rotary speed regulation to a relatively low drum speed. It will be noted however that there is the disadvantage here that, with a high degree of drum filling, as a consequence of a correspondingly increased mass moment of inertia and at a relatively high nominal rotary speed, the fluctuations in rotary speed which occur around the nominal rotary speed become so slight that they can scarcely still be detected in terms of the measuring procedure involved.
  • a method of determining a characteristic value for an imbalance of a laundry drum that is electrically driven about a substantially horizontal axis comprises the following:
  • the objects of the invention are achieved in that the direct current consumption of the motor in the circuit from the direct current intermediate circuit to the inverter is taken as the basis, directly from a high drum speed, with hard rotary speed regulation, that is to say a constant rotary speed. That direct current measurement result is well blocked off in relation to the mains network as a consequence of the rectifier circuit upstream of the direct current intermediate circuit, that is to say interference phenomena at the network side are practically no longer superimposed on that direct current measurement result, and that therefore also permits reproducible measurement of very small temporal fluctuations in the motor power which is drawn in dependence on imbalance.
  • the product of a d.c. voltage at the output of the direct current intermediate circuit and direct current from the direct current intermediate circuit into the inverter is determined in a power measuring circuit.
  • the current fluctuation is detected at a temporarily raised voltage. It is advantageous if the voltage is raised to mains network voltage.
  • the power or current measurement is effected in the spin mode at an elevated drum speed prior to a possible transition to a maximum drum speed.
  • the fluctuation in rotary speed in the course of a revolution with a high mass inertia is scarcely still measurable and recording of the periodic fluctuation in the ac power taken by the drum drive from the domestic mains network is dominatingly superimposed by the mains network frequency and other network interference influences
  • the fluctuation, which is at high frequency in dependence on drum speed, of the power consumption of the washing machine motor is implemented downstream of the direct current intermediate circuit prior to the feed thereof into the inverter for producing the rotary field in the motor, where product formation from the current and the voltage for imbalance measurement by determining power is blocked off in relation to mains network interference effects by the high capacitance of the direct current intermediate circuit.
  • FIGURE of the drawing is a partly schematic partly diagrammatic view illustrating the location of power measurement in the course of supplying a drive motor for a laundry drum which is subject to imbalance.
  • washing machine 11 is equipped for treating laundry 12 in its washing solution tank with a perforated drum 13 .
  • the drum 13 can in this case be driven in rotation by a rotating field motor 14 about a substantially horizontal axis 15 .
  • the rotating field for that purpose is impressed on the motor 14 by way of alternately passing current through typically three stator winding systems 16 which are each connected to a half-bridge circuit 17 for switching and pole changing of a stator magnetomotive force.
  • the entirety of the bridge circuits 17 therefore acts as an inverted rectifier or inverter 18 , whose switching sections are cyclically switched by a general control system 19 for predetermining the direction and speed of rotation of the drum drive motor 14 .
  • the control system 19 operates as a rotary speed regulator if the actual rotary speed 20 is fed back thereto in order to compare it to a reference rotary speed 21 which is predetermined manually or from a washing program.
  • the feed to the washing machine motor 14 and thus the inverter 18 connected upstream thereof is implemented from the alternating current domestic mains network 22 (a.c. mains) by way of a converter 23 with a rectifier circuit which is buffered towards the load by a large capacitor 25 of a so-called direct current intermediate circuit 26 .
  • power measurement is not effected at the connection of the consumer to the alternating current mains network 22 but in the direct current supply of the inverter 18 downstream of the direct current intermediate circuit 26 .
  • the vector product is formed from the d.c. voltage 27 and the direct current 28 for feeding the motor 14 by way of the inverter 18 , and switched to the control system 19 , as power 29 which fluctuates in dependence on time.
  • That measurement procedure can also be carried out reproducibly and without interference even at a very high drum speed 13 and with a power consumption that correspondingly fluctuates at high frequency, because any disturbing network influences are reliably kept away from vectorial product formation in the power measuring circuit 30 by the converter 23 and the low pass effect of the direct current intermediate circuit 26 .
  • a development according to the invention that has proven to be particularly advantageous provides that current measurement is effected downstream of the direct current intermediate circuit 26 for determining the imbalance at high drum speeds if the motor voltage 27 in that case is temporarily increased, preferably temporarily switched to the greatest value (that is to say to mains network voltage).
  • the motor voltage 27 in that case is temporarily increased, preferably temporarily switched to the greatest value (that is to say to mains network voltage).
  • the characteristic of the torque and thus the electrical power P consumed or the motor current 28 falls more steeply in relation to the rotary speed; the fall is correspondingly steeper, the higher the applied motor voltage 27 is.
  • the rotary speed fluctuates due to imbalance, the resulting fluctuation in the current 28 drawn by the drive motor 14 for the drum 13 occurs to a correspondingly greater degree, the higher that the applied motor voltage 27 is at the time.
  • the temporary increase in voltage at a high rotary speed results in a marked, reproducibly detectable current fluctuation di/dt in spite of imbalance in the drum loading being only slight—but perhaps nonetheless already being structural
  • the rotary speed-dependent fluctuation in current consumption di/dt of the washing machine motor 14 is implemented from the direct current intermediate circuit 26 prior to the feed into the inverter 18 for producing the rotary field in the motor 14 , where the imbalance-dependent current fluctuation di/dt is blocked off in relation to mains network interference effects by the high capacitance 25 of the direct current intermediate circuit 26 . That current fluctuation di/dt which is to be measured for determining imbalance at a high rotary speed can be shown still more clearly if it is detected at a motor voltage 27 which is temporarily increased for that purpose.

Landscapes

  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Control Of Washing Machine And Dryer (AREA)
  • Testing Of Balance (AREA)
  • Treatment Of Fiber Materials (AREA)
  • Centrifugal Separators (AREA)
  • Drying Of Solid Materials (AREA)
US11/040,805 2002-07-26 2005-01-21 Method of determining the imbalance of a laundry drum Expired - Fee Related US6973392B2 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10234053A DE10234053C1 (de) 2002-07-26 2002-07-26 Verfahren zum Bestimmen der Unwucht einer Wäschetrommel
DE10234053.6 2002-07-26
PCT/EP2003/007388 WO2004013401A2 (de) 2002-07-26 2003-07-09 Verfahren bestimmen der unwucht einer wäschetrommel

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2003/007388 Continuation WO2004013401A2 (de) 2002-07-26 2003-07-09 Verfahren bestimmen der unwucht einer wäschetrommel

Publications (2)

Publication Number Publication Date
US20050143940A1 US20050143940A1 (en) 2005-06-30
US6973392B2 true US6973392B2 (en) 2005-12-06

Family

ID=29265417

Family Applications (1)

Application Number Title Priority Date Filing Date
US11/040,805 Expired - Fee Related US6973392B2 (en) 2002-07-26 2005-01-21 Method of determining the imbalance of a laundry drum

Country Status (7)

Country Link
US (1) US6973392B2 (de)
EP (1) EP1525349B1 (de)
AT (1) ATE490362T1 (de)
AU (1) AU2003253042A1 (de)
CA (1) CA2492551C (de)
DE (2) DE10234053C1 (de)
WO (1) WO2004013401A2 (de)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060238152A1 (en) * 2003-06-11 2006-10-26 Elio Marioni Method for detecting unbalanced conditions of a rotating load driven by a synchronous motor and for controlling said motor
US20080156094A1 (en) * 2006-12-27 2008-07-03 General Electric Company Systems and methods for detecting out-of-balance conditions in electronically controlled motors
US20130119909A1 (en) * 2005-08-16 2013-05-16 Whirlpool Corporation Method of detecting an off-balance condition of a clothes load in a washing machine

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7905122B2 (en) * 2003-04-28 2011-03-15 Nidec Motor Corporation Method and system for determining a washing machine load unbalance
DE102004053216B3 (de) * 2004-06-18 2006-02-09 Diehl Ako Stiftung & Co. Kg Vorrichtung zur Erfassung einer Schwingbewegung einer Wäschetrommel
DE102006017530A1 (de) * 2006-04-13 2007-10-18 BSH Bosch und Siemens Hausgeräte GmbH Maschine zum Waschen und/oder Trocknen von Wäsche sowie Verfahren zum Erfassen von Unwuchtparametern
DE102009001271A1 (de) 2009-03-02 2010-09-09 BSH Bosch und Siemens Hausgeräte GmbH Verfahren zum Ermitteln der Beladung und/oder der Unwucht einer Wäschetrommel einer Waschmaschine und entsprechende Schaltungsanordnung
US8291764B2 (en) * 2009-08-14 2012-10-23 Lenz Michael A W Method and apparatus for in situ unbalance and corrective balance determination for a non-vertical axis rotating assembly
DE102009028810A1 (de) 2009-08-21 2011-02-24 BSH Bosch und Siemens Hausgeräte GmbH Verfahren zum Ermitteln einer Unwucht bei einer Wäschetrommel einer Waschmaschine im Schleuderbetrieb, Antriebsvorrichtung und Waschmaschine mit einer Antriebsvorrichtung
DE102010027158B4 (de) 2010-07-14 2012-06-06 Diehl Ako Stiftung & Co. Kg Wäschebehandlungsgerät
DE102010042492A1 (de) 2010-10-15 2012-04-19 BSH Bosch und Siemens Hausgeräte GmbH Antriebsvorrichtung zum Antreiben einer Komponente eines Hausgeräts, Hausgerät und Verfahren zum Betreiben eines Hausgeräts
DE102012021747B4 (de) 2012-06-26 2021-01-28 Diehl Ako Stiftung & Co. Kg Verfahren und Vorrichtung zum Erkennen einer Umwucht in einem Wäschebehandlungsgerät
JP6634602B2 (ja) * 2016-05-19 2020-01-22 パナソニックＩｐマネジメント株式会社 洗濯機
JP6681542B2 (ja) * 2016-05-27 2020-04-15 パナソニックＩｐマネジメント株式会社 洗濯機
JP6681541B2 (ja) * 2016-05-27 2020-04-15 パナソニックＩｐマネジメント株式会社 洗濯機

Citations (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2917175A (en) 1959-01-22 1959-12-15 Gen Electric Unbalance sensing arrangement for machines having a centrifugal liquid extraction step
EP0275862A2 (de) 1987-01-15 1988-07-27 AUSTRIA Antriebstechnik G. Bauknecht Aktiengesellschaft Einrichtung zur Unwuchterkennung
EP0313339A1 (de) 1987-10-19 1989-04-26 American Laundry Machinery, Inc. Unwuchtkontrolle für Waschmaschinen
DE3822924C1 (de) 1988-07-07 1989-11-23 Miele & Cie Gmbh & Co, 4830 Guetersloh, De
JPH0391511A (ja) 1989-09-04 1991-04-17 Mitsubishi Petrochem Co Ltd α―オレフイン重合用触媒及びその使用
US5070565A (en) * 1989-04-17 1991-12-10 Emerson Electric Co. Unbalanced load detection system and method for a household appliance
DE4101341A1 (de) 1991-01-18 1992-07-23 Ako Werke Gmbh & Co Frequenzumrichter fuer einen asynchron-drehstrommotor
JPH04314496A (ja) 1991-04-12 1992-11-05 Toshiba Corp 洗濯機
DE4208989A1 (de) 1992-03-20 1993-09-23 Philips Patentverwaltung Verfahren zur detektion und kompensation einer unwucht bei einem durch einen motor angetriebenen rotor
DE4431846A1 (de) 1994-09-07 1996-03-14 Ako Werke Gmbh & Co Verfahren zum beladungsabhängigen Steuern und/oder Regeln einer Waschmaschine oder eines Wäschetrockners
US5677606A (en) * 1994-10-21 1997-10-14 Mitsubishi Denki Kabushiki Kaisha Device and method for detecting unbalanced condition in a load driven by a motor
EP1045062A2 (de) 1999-03-26 2000-10-18 Samsung Electronics Co., Ltd. Waschmaschine
DE19918331A1 (de) 1999-04-22 2000-10-26 Bsh Bosch Siemens Hausgeraete Verfahren und Vorrichtung zur Detektion von Unwuchten bei einem durch einen bürstenlosen Elektromotor angetriebenen Rotor
US20020030462A1 (en) * 2000-07-14 2002-03-14 Hideo Matsushiro Apparatus and method for driving a brushless motor
US6418581B1 (en) * 1999-06-24 2002-07-16 Ipso-Usa, Inc. Control system for measuring load imbalance and optimizing spin speed in a laundry washing machine
US20030056302A1 (en) * 2001-09-21 2003-03-27 Maytag Corporation Unbalance detection system for a washing machine
US6640372B2 (en) * 2000-06-26 2003-11-04 Whirlpool Corporation Method and apparatus for detecting load unbalance in an appliance
US6642690B2 (en) * 2001-05-10 2003-11-04 Lg Industrial Systems Co., Ltd. Method for measuring phase current for inverter control apparatus using single current sensor and apparatus therefor
US6715175B2 (en) * 2000-06-26 2004-04-06 Whirlpool Corporation Load unbalanced prediction method and apparatus in an appliance

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IT1038355B (it) * 1975-05-22 1979-11-20 Ire Spa Procedimento e macchina automatica per lavare e centrifugare la biancheria

Patent Citations (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2917175A (en) 1959-01-22 1959-12-15 Gen Electric Unbalance sensing arrangement for machines having a centrifugal liquid extraction step
EP0275862A2 (de) 1987-01-15 1988-07-27 AUSTRIA Antriebstechnik G. Bauknecht Aktiengesellschaft Einrichtung zur Unwuchterkennung
EP0313339A1 (de) 1987-10-19 1989-04-26 American Laundry Machinery, Inc. Unwuchtkontrolle für Waschmaschinen
DE3822924C1 (de) 1988-07-07 1989-11-23 Miele & Cie Gmbh & Co, 4830 Guetersloh, De
US5070565A (en) * 1989-04-17 1991-12-10 Emerson Electric Co. Unbalanced load detection system and method for a household appliance
JPH0391511A (ja) 1989-09-04 1991-04-17 Mitsubishi Petrochem Co Ltd α―オレフイン重合用触媒及びその使用
DE4101341A1 (de) 1991-01-18 1992-07-23 Ako Werke Gmbh & Co Frequenzumrichter fuer einen asynchron-drehstrommotor
JPH04314496A (ja) 1991-04-12 1992-11-05 Toshiba Corp 洗濯機
DE4208989A1 (de) 1992-03-20 1993-09-23 Philips Patentverwaltung Verfahren zur detektion und kompensation einer unwucht bei einem durch einen motor angetriebenen rotor
DE4431846A1 (de) 1994-09-07 1996-03-14 Ako Werke Gmbh & Co Verfahren zum beladungsabhängigen Steuern und/oder Regeln einer Waschmaschine oder eines Wäschetrockners
US5677606A (en) * 1994-10-21 1997-10-14 Mitsubishi Denki Kabushiki Kaisha Device and method for detecting unbalanced condition in a load driven by a motor
EP1045062A2 (de) 1999-03-26 2000-10-18 Samsung Electronics Co., Ltd. Waschmaschine
US6240586B1 (en) * 1999-03-26 2001-06-05 Samsung Electronics Co., Ltd. Unbalance detecting device and method of washing machine
DE19918331A1 (de) 1999-04-22 2000-10-26 Bsh Bosch Siemens Hausgeraete Verfahren und Vorrichtung zur Detektion von Unwuchten bei einem durch einen bürstenlosen Elektromotor angetriebenen Rotor
US6418581B1 (en) * 1999-06-24 2002-07-16 Ipso-Usa, Inc. Control system for measuring load imbalance and optimizing spin speed in a laundry washing machine
US6564592B2 (en) * 1999-06-24 2003-05-20 Ispo-Usa, Inc. Control system for measuring load imbalance and optimizing spin speed in a laundry washing machine
US6640372B2 (en) * 2000-06-26 2003-11-04 Whirlpool Corporation Method and apparatus for detecting load unbalance in an appliance
US6715175B2 (en) * 2000-06-26 2004-04-06 Whirlpool Corporation Load unbalanced prediction method and apparatus in an appliance
US20020030462A1 (en) * 2000-07-14 2002-03-14 Hideo Matsushiro Apparatus and method for driving a brushless motor
US6642690B2 (en) * 2001-05-10 2003-11-04 Lg Industrial Systems Co., Ltd. Method for measuring phase current for inverter control apparatus using single current sensor and apparatus therefor
US20030056302A1 (en) * 2001-09-21 2003-03-27 Maytag Corporation Unbalance detection system for a washing machine

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060238152A1 (en) * 2003-06-11 2006-10-26 Elio Marioni Method for detecting unbalanced conditions of a rotating load driven by a synchronous motor and for controlling said motor
US7471054B2 (en) * 2003-06-11 2008-12-30 Askoll Holding S.R.L. Method for detecting unbalanced conditions of a rotating load driven by a synchronous motor and for controlling said motor
US20130119909A1 (en) * 2005-08-16 2013-05-16 Whirlpool Corporation Method of detecting an off-balance condition of a clothes load in a washing machine
US8918937B2 (en) * 2005-08-16 2014-12-30 Whirlpool Corporation Method of preventing motor overload in a washing machine
US20080156094A1 (en) * 2006-12-27 2008-07-03 General Electric Company Systems and methods for detecting out-of-balance conditions in electronically controlled motors

Also Published As

Publication number Publication date
US20050143940A1 (en) 2005-06-30
EP1525349B1 (de) 2010-12-01
CA2492551C (en) 2007-11-13
AU2003253042A1 (en) 2004-02-23
WO2004013401A2 (de) 2004-02-12
DE10234053C1 (de) 2003-11-20
CA2492551A1 (en) 2004-02-12
DE50313295D1 (de) 2011-01-13
EP1525349A2 (de) 2005-04-27
WO2004013401A3 (de) 2004-04-29
ATE490362T1 (de) 2010-12-15

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